Silnov is under investigation by the Athletics Integrity Unit, which handles international doping cases in track and field. Neither he nor the AIU has revealed the nature of the allegation against him.
Russia has been banned from international track competitions since 2015 for widespread doping, but dozens from the country are allowed to compete as neutral athletes. That ban was extended Sunday when the IAAF expressed concern about "apparent backsliding" on doping reforms.
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